Last week, I invited Fool co-founder David Gardner into our brand-new Motley Fool studio space here in Alexandria, Va. We spent nearly an hour talking about the state of the retail investor here in 2013, his investing philosophy, and his current thinking on a half-dozen specific stocks in his Supernova universe. (You can view the entire interview here.)

One of the stocks we discussed was Apple (NASDAQ:AAPL). David admitted that he grew bullish on Apple fairly late in its massive run-up -- he first recommended it to Stock Advisor subscribers almost five years ago to the day (Jan. 18, 2008), when it traded for $169.

But even after Apple's incredible 10-year gains, it's still a "core" and "best buy now" in his service; he believes it has the marks of a great business for the next five years. How can it keep the magic going?

David told me it's because of Apple's massive cash hoard, its remarkable culture, and the strength of its brand among consumers. You can watch his answer in the video below (run time: 2:26).